1. Related Applications
The subject matter of the present application is related to the subject matter of the applications "Automatic Colorant Mixing Method and Apparatus" and "Dynamic Device Independent Image Correction Method and Apparatus" filed by the same assignee, which are incorporated herein by reference.
2. Field of Invention
The present invention relates to controlling the output of a marking device, and in particular, to a device independent color controller and method that uses information detected from a color output image to control individual color separations.
3. Description of Related Art
Customers continue to demand faster, higher quality and more sophisticated marking devices (e.g., printers, copiers, etc.). Additionally, customers demand the ability to reproduce their desired input images to achieve accurate output that does not vary over time (e.g., between pages or when output again at a later time) or among various marking devices (e.g., among various printers on a network, between home and office marking devices, etc.). These considerations are more difficult to achieve with color marking devices because of the greater number of variables involved and the sensitivity of these devices to environmental conditions.
In addition to controlling other variables of the marking device subsystem, controlling the device independent marking device tone reproduction curves (TRCs) for a color marking device would also be desirable. Tone reproduction curves are stored plots of an input parameter value versus an output parameter value. A TRC is a monitonically increasing marking device function in input-output contone space, input-output density space or input-output byte space, or combinations thereof. In other words, a TRC indicates the value of the output parameter for a specific device that must be used to reproduce the input parameter.
It would be desirable to use controlled tone reproduction curves at different steps in the reproduction process. The controlled tone reproduction curve for any one of the marking device color separations would account for the variability in reproducing that color in the marking device.
Moreover, it would be desirable to provide controlled of tone reproduction curves on a real time basis, either between jobs or within a single job, to account for ongoing marking device variability.